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Overview and Calendar for 2017

Overview

Let's look at occultations in 2017!

An occultation is a phenomenon where a star is hidden by the Moon moving through the night sky. In 2017 you can see the occultation of the 1st magnitude star Aldebaran in the constellation Taurus and the 1st magnitude star Regulus in the constellation Leo. In particular, conditions during the occultation of Aldebaran on January 9 are favorable and it can be observed from throughout Japan.

Among the 3 major meteor showers, the Perseid Meteor Shower is ill-suited for observation because the Moon is bright at the peak time. The timing of the peak and the phase of the Moon for the Quadrantid Meteor Shower (January) and the Geminid Meteor Shower (December) are favorable.

Many astronomical events occur in 2017, for example, the occultation of Mercury on July 25, when Mercury gets concealed by the Moon and the partial lunar eclipse on August 8.

January

1New Year’s Day [Ganjitsu] (national holiday)
2Holiday
3Quadrantid Meteor Shower peaks around 23:00. (For Japan, the best visibility will be before dawn on the 4th. About 35 meteors per hour are expected. Because there is no moonlight and the timing of the maximum is not so bad, conditons are relatively good.)
4Earth passes perihelion
6First Quarter Moon
8Mercury at stationary point
9Coming-of-Age Day [Seijin-no-hi] (national holiday) / Occultation of Aldebaran
12Full Moon / Greatest Eastern Elongation of Venus
19Greatest Western Elongation of Mercury
20Last Quarter Moon
28New Moon

Februray

4First Quarter Moon
7Jupiter at stationary point
11Full Moon / National Foundation Day [Kenkoku-Kinen-no-hi] (national holiday)
17Venus at Greatest Brillancy
19Last Quarter Moon
26Annular solar eclipse (not visible from Japan) Reference: Local Prediction of the Solar Eclipse / New Moon

March

2Neptune at conjunction / Venus at stationary point
5First Quarter Moon
7Mercury at superior conjunction
12Full Moon
20Vernal Equinox Day [Shunbun-no-hi] (national holiday) / Vernal equinox (Sun’s ecliptic longitude 0°)
21Last Quarter Moon
25Venus at inferior conjunction
28New Moon

April

1Greatest Eastern Elongation of Mercury / Occultation of Aldebaran
4First Quarter Moon
6Saturn at stationary point
8Jupiter at opposition
10Mercury at stationary point
11Full Moon
13Venus at stationary point
14Uranus at conjunction
19Last Quarter Moon
20Mercury at inferior conjunction
22Lyrid Meteor Shower peaks around this time(The best visibility is before dawn on the 23nd. About 5 meteors per hour are expected. Because there is no moonlight and the timing of the maximum is good, conditions are good.)
26New Moon
29Showa Day [Showa-no-hi] (national holiday)
30Venus at Greatest Brillancy

May

2Mercury at stationary point
3First Quarter Moon / Constitution Memorial Day [Kenpou-Kinen-bi] (national holiday)
4Greenery Day [Midori-no-hi] (national holiday)
5Children’s Day [Kodomo-no-hi] (national holiday)
6η(Eta) Aquarid Meteor Shower peaks around this time (The best visibility will be before dawn for the 2~3 days around this date. About 5 meteors per hour are expected. Conditions are good after the Moon sets after Midnight.)
11Full Moon
18Greatest Western Elongation of Mercury
19Last Quarter Moon
26New Moon

June

1First Quarter Moon
3Greatest Western Elongation of Venus
9Full Moon (This year’s smallest Full Moon)
10Jupiter at stationary point
15Saturn at opposition
17Last Quarter Moon / Neptune at stationary point
21Mercury at superior conjunction / Summer solstice (Sun’s ecliptic longitude 90°)
24New Moon

July

1First Quarter Moon
4Earth passes aphelion
9Full Moon
17Last Quarter Moon /Ocean Day [Umi-no-hi](national holiday)
23New Moon
25Occultation of Mercury
27Mars at conjunction
30Greatest Eastern Elongation of Mercury / Aquarid δ (Delta) Meteor Shower peaks around this time (The best visibility is after midnight for 6~7 days around this date. About 5 meteors per hour are expected. Conditions are good after the Moon sets around Midnight.)
31First Quarter Moon

August

3Uranus at stationary point
8Partial Lunar Eclipse Reference: Local Prediction of Lunar Eclipse / Full Moon
11Mountain Day [Yama-no-hi](national holiday)
12Mercury at stationary point
13The Perseid Meteor Shower peaks around 4:00(The best time for viewing is before dawn on the 13th. On the order of 35 meteors per hour are expected. The Moon is bright, so conditions are bad.)
15Last Quarter Moon
22Total solar eclipse (not visible from Japan)  Reference: Local Prediction of the Solar Eclipse / New Moon
26Saturn at stationary point
27Mercury at inferior conjunction
28Traditional tanabata (traditional star festival)
29First Quarter Moon

September

5Mercury at stationary point / Neptune at opposition
6Full Moon
12Greatest Western Elongation of Mercury
13Last Quarter Moon
18Respect-for-the-Aged Day [Keiro-no-hi ](national holiday)
20New Moon
23Autumnal Equinox Day [Shubun-no-hi] (national holiday)/ Autumn equinox (Sun’s ecliptic longitude 180°)
28First Quarter Moon

October

4Chushu Moon
6Full Moon
8The October Draconid Meteor Shower peaks around this time. (The best time to observe is after sunset on the 8th. On the order of 4 meteors per hour are expected. Conditions are good for about 1 hour from when it gets dark after sunset until the Moon rises.)
9Mercury at superior conjunction / Health-Sports Day [Taiiku-no-hi] (national holiday)
10Occultation of Aldebaran (Mainly Northern Japan) / The Southern Taurid Meteor Shower peaks around this time. (The best time to observe is before midnight in the latter part of October, when there is no effect from moonlight. On the order of 2 meteors per hour are expected.)
12Last Quarter Moon
20New Moon / Uranus at opposition
21The Orionid Meteor Shower peaks around this time. (The best time to observe is before dawn for about 4~5 days around this date. On the order of 5 meteors per hour are expected. There is no moonlight, so the conditions are very good.)
27Jupiter at conjunction
28First Quarter Moon

November

3Culture Day [Bunka-no-hi](national holiday)
4Full Moon
11Last Quarter Moon
12Occultation of Regulus / Northern Taurid Meteor Shower peaks around this time.(The best time to observe is before midnight in the latter part of November, when there is no effect from moonlight. On the order of 2 meteors per hour are expected.)
18New Moon / Leonid Meteor Shower peaks around this time. (The best time for viewing is before dawn on the 18th. On the order of 2 meteors per hour are expected. Because there is no moonlight and the timing of the maximum is not so bad, conditons are relatively good.)
23Neptune at stationary point / Labor Thanksgiving Day [Kinro-kansha-no-hi] (national holiday)
24Greatest Eastern Elongation of Mercury
27First Quarter Moon

December

3Mercury at stationary point
4Full Moon(This year’s largest Full Moon)
10Last Quarter Moon
13Mercury at inferior conjunction
14Geminid Meteor Shower peaks around 16:00(The best time to observe is after midnight on the morning of the 14th. On the order of 40 meteors per hour are expected. Because there is almost no effect from moonlight and the timing of the maximum is not so bad, conditons are relatively good.)
18New Moon
22Saturn at conjunction / Winter solstice (Sun’s ecliptic longitude 270°)
23Mercury at stationary point / Emperor’s Birthday [Tennou-Tanjyobi] (national holiday)
26First Quarter Moon

The days for the peak activities of the meteor showers are based on the predictions of IMO (the International Meteor Organization). The standard number of meteors appearing listed for a meteor shower is the maximum number per hour at the peak time that a normal person can observe if the sky is dark enough to see the Milky Way. Therefore, the number of meteors can become a fraction of this number when observing in city lights or at a time other than the peak. On the other hand, a severalfold increase in the number of meteors can be seen based on the sky condition and observers' proficiency.